A burglar who enters homes while people are sleeping apparently broke into three Arvada, Colo., homes just after 2:30 a.m. Thursday.

Police said the same burglar is believed to have entered three different residences in Skyline Estates through unlocked doors and a window.

While police were responding to one of the burglaries, a man was spotted outside another home in the area and chased by an Arvada police officer. A search of the area failed to locate him.

Arvada detectives are coordinating their investigation with Jefferson County and Wheat Ridge, where similar burglaries have been reported. It’s believed the same man has committed more than 10 burglaries in the three jurisdictions since late last year.

“No matter where you live, homeowners should make sure that their doors and windows are always locked, especially before they go to bed,” said Gary Creager, the commander of the Arvada Police Department.

Creager said that residents should take note of any suspicious people in their neighborhood, especially in the early morning hours.

Anyone with information about these crimes should call their local police department. To reach the Arvada Police Department call (720) 898-6900.